Drop Fedora support

Fedora support is never tested, and has been unmaintained for a while.
Because we don't expect any actual user using OpenStack on Fedora, this
change drops support for Fedora directly.

Change-Id: I47b68064df58fb9874d1d069619611a1e8a51a60

metadata.json

@@ -37,12 +37,6 @@
                 "11"
             ]
         },
-        {
-            "operatingsystem": "Fedora",
-            "operatingsystemrelease": [
-                "24"
-            ]
-        },
         {
             "operatingsystem": "RedHat",
             "operatingsystemrelease": [

releasenotes/notes/drop-fedora-bd83080aef24213a.yaml

@@ -0,0 +1,4 @@
+---
+upgrade:
+  - |
+    Fedora is no longer supported.